Q: On my car’s dashboard I have a gauge that is labeled “RPM”. What does RPM represent?
A: RPM stands for Revolutions Per Minute. This instrument gauge is called a tachometer. The tachometer measures the number of times (per minute) the crankshaft makes a complete revolution. This is also referred to as engine speed. Look at the gauge and look for numbers in red or a red line. When running the engine, do not let the engine operate in the red areas. Running an engine in or near the red line puts excessive strain on engine components, could damage the engine, or ultimately shorten its life.